SEGA Casino is the best overall casino package. The Texas Hold'em is very fun (and fast paced, for after you fold out), but the AI is easy to beat if you keep to very basic stratagy. If you want just Poker, I'd get World Series of Poker 2008: Battle for the Bracelets... it's got the best AI for DS poker games, and great variety of game types... just wish it had WFC play.